The slow count brought back memories of the bitterly contested recount in 2000.

The Sunshine State's famous "hanging chads" sparked a crisis in that year's Bush-Gore election, eventually leading to a Supreme Court ruling that installed George W Bush in the White House.

The figures released by the Florida state department suggest Mr Obama won 4,236,032 votes out of a total of 8,471,095 cast - 73,858 more than Mr Romney and well above the 0.5% difference which would have triggered an automatic recount.

The result will not come as a surprise to either President Obama or Governor Romney - it has been assumed that the president would win since late on Tuesday, says the BBC's Zoe Conway in Washington.

But it is significant nonetheless, our correspondent adds, as it further strengthens President Obama's negotiating position when it comes to doing deals with Republicans in Congress.

And because there are so many Latino voters in the state, the result will also reinforce the message that Republicans need to do more to win the Hispanic vote, our correspondent says.

Exit polls suggest that Florida's Cuban Americans voted for the Democratic party in record numbers.

Tax cliff

The newly re-elected Mr Obama has said the wealthy must pay more taxes under any political settlement to avert a looming budget crisis.

Image caption
Obama is using his renewed mandate to address the budget deficit

He has urged Congress to act against the so-called fiscal cliff, a package of tax rises and spending cuts due early next year.

But in a duelling news conference on Friday, Republican House Speaker John Boehner said tax rises would not be acceptable.

Budget analysts warn the US will tip into recession unless a deal is struck.

Mr Obama has repeatedly called for the affluent to pay more, but such a plan is anathema to Republicans.

The fiscal cliff would see the expiry of George W Bush-era tax cuts at the end of 2012, combined with automatic, across-the-board reductions to military and domestic spending.

Queues and challenges

Florida's problems began even before election day, with lengthy queues reported during the early-voting period.

Democrats launched a legal challenge against a Republican-backed measure to limit the period during which voters could cast ballots before the election, from 14 days to eight.

They said it was a blatant attempt to suppress Democratic turnout - Florida's African-American voters have tended to cast ballots early in previous elections.

But Governor Rick Scott said the measure, passed by the state's Republican-controlled legislature in 2011, aimed to limit voter fraud.

The early-voting period officially ended last Saturday. Election supervisors in Miami-Dade and other counties did open up voting for several hours on Sunday.

But after being swamped by voters, one polling office in Miami-Dade County temporarily shut its doors. Some in line began to shout: "Let us vote!"

There was also a technical error with an automated phone system that told more than 12,500 voters in another county that the election was on Wednesday.

Florida was not alone in reports of lengthy election day queues. Voters waited for hours in states such as Virginia, New York and Washington DC.